We will have our monthly site visit (always the first Thursday of the month from 3:30-4:30) on Thursday, July 1st. Since last month, we have completed most site utilities, poured foundation footings, and completed the main site retaining wall. This month, we will be discussing the complicated three dimensional underground construction we’ve had to do with site utilities, the ground source wells and manifolds, foundations, all in an incredibly tight site. We will also talk about our use of McDonald’s fryer oil for concrete form release (and even let you smell it!), as well as several recycled materials like drainage board we’re using in the project. If you missed last month, we’ll also do an overview of how the ground source well field system works. Click here for directions to the site.

Join Eastside Greendrinks on July 15th at 5:PM at Vista Park, located on 10th Avenue NE within Issaquah Highlands. Come and connect with green people, green businesses and events in your community. Jobsite tour of zHome will be included. Come check out the progress!

This is a FREE event but a $5.00 donation is suggested. Beer, wine and light appetizers will be served.

Concrete forms are typically sprayed with diesel oil to allow the form boards to come easily away from the forms once the concrete has dried.  Check out this short video of Nick Nied of Ichijo USA discussing the recycled fry oil we used instead!

Dennis Rominger, Puget Sound Energy

Dennis Rominger is Puget Sound Energy’s representative on zHome.  He’s been heavily involved in the project for years now, and has been a very important person in its life.  Right now Dennis is taking the lead on college and youth zHome education and has been doing a terrific job.  He recently did a class for Shoreline Community College’s zero energy class and it was great to hear another perspective on our design process and the importance of the project.

Dennis is a great guy, and a ton of fun to work with.  He is a very hard worker and a project manager par excellence.  He is very passionate about energy efficiency and getting real change on the ground.  There are a lot of dreamers involved in zHome, and even though Dennis dreams with the best of us, he is also pragmatic and always thinking about getting the job actually done.  We are very lucky to have him involved in the project!

One of the zHome materials benchmarks is for all concrete to include 30 percent flyash by volume.  This is an aggressive percentage, reflecting the nature of zHome’s pushing the envelope. 

Flyash is the byproduct from coal burning power plants.  Flyash is a recycled material that reduces the need for cement.  Another benefit to using flyash beyond simply reducing material use is that the production of cement produces a significant amount of CO2 – so using less is good.

High flyash concrete is different than typical cement.  It is stickier and harder to form and work.  It takes longer to cure, which particularly in structural situations can mess with your timeline.  On the upside, in addition to its environmental benefits, it has less voids than typical concrete (the flyash is like little ball bearings and helps the concrete flow) and is stronger once fully cured. 

Closeup of 30% flyash wall - almost void free.

Centralia power plant, source of our flyash

An interesting sidenote is that flyash locally has historically come from the Centralia power plant.  However, during the boom times, local demand for flyash resulted in it being brought in by rail from Alberta, which created its own carbon issues.  Now, with construction significantly reduced, we are back to Centralia flyash being easily available.

Twenty five folks joined us on site today to learn the latest on zHome construction – the groundsource wells, an overview of the groundsource system, working with high flyash concrete, and vegetable oil low toxicity form releaser.  Our next on-site class will be on July 1, and continue on the first Thursday of every month through construction.  Come join us!